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Article
Study of Wear Behavior of Aluminum Alloy Matrix Nanocomposites Fabricated by Powder Technology
دراسة سلوك البلى لمواد متراكبة نانوية ذات أساس المنيوم مصنعة بتكنلوجيا المساحيق

Authors: Muna Khethier Abbass --- Mohammed Jabber Fouad
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2014 Volume: 32 Issue: 7 Part (A) Engineering Pages: 1720-1732
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In the present work, the dry sliding wear behavior of Al-12wt%Si matrix nanocomposites reinforced with single addition of 4wt.% Al2O3 or 4wt.%TiO2 nanoparticles, and with hybrid addition of 4wt% (Al2O3 +TiO2) nano particles is investigated. All nanocomposites samples were fabricated by powder technology by mechanical milling of the base alloy (Al-12wt%Si) powder and nanopowders of Al2O3 and TiO2, followed by cold pressing at 100bar and sintering at 520 oC for 90min. Vickers hardness test was done by using Vickers hardness tester. Archimedes technique was used to measure the density of sintered samples and porosity calculated as physical tests of sintered samples. Also AFM, SEM were used to investigate the morphology of mixed powders and nanocomposites samples. Pin – on Disc wear tests were carried out at room temperature under dry sliding conditions with using different normal loads and sliding times. Worn surface micrographs were investigated based on the optical and scanning electron microscopy observations of wear tracks and wear debris morphology. It has been found that nanocomposite with 4wt% Al2O3 nanoparticles shows the highest hardness than other nanocomposites. It was observed that the wear rate or weight loss of the base alloy and nanocomposite samples increases with the increase in applied load and sliding time. But the nanocomposites samples showed lower wear rate than the base alloy within the same conditions.

يدرس البحث الحالي خواص البلى الانزلاقي الجاف لمواد متراكبة نانوية ذات اساس من سبيكة الألمنيوم-12%سليكون مقواة بدقائق نانوية من4 % الومينا او التيتانيا او( كإضافة مشتركة ). وقد تم تصنيع السبيكة الأساس والمواد المتراكبة النانوية بطريقة تكنلوجيا المساحيق حيث أجريت عملية الخلط الميكانيكي للمساحيق المختلفة من مسحوق سبيكة الالمنيوم-12% سليكون ومسحوق الالومينا و التيتانيا ثم أجريت عملية الكبس على البارد بضغط 100بار والتلبيد عند درجة حرارة520 ْم لمدة 90 دقيقة. وقد تم قياس الصلادة الڨيكرية وقياس الكثافة والمسامية للنماذج الملبدة . كذلك تم استعمال مجهر القوة الذرية والمجهر الالكتروني الماسح لدراسة مورفولوجي وفحص المساحيـق المخلوطة وبعض المواد المتراكبة النانوية الهجينة المصنعة. وقد اوضحت الصور المأخوذة بمجهر القوة الذرية لخليط المساحيق من السبيكة الاساس والدقائق النانوية المشتركة من الالومينا و التيتانيا حصول خلط جيد بيـن المساحيـق المختـلفة وتوزيع متجانس للدقائق النانوية في ارضية السبيكة . وتم أجراء اختبار البلى من نوع المسمار على القرص تحت ظروف الانزلاق الجاف مع تغيـيـر الاحمال المسلطة و أزمان الانزلاق لكل النماذج المحضرة . وتم استعمال المجهر الضوئي والمجهر الالكتروني الماسح لدراسة طوبوغرافية سطوح البلى وملاحظة خطوط البلى وحطام البلى. وان المواد المتراكبة النانوية المقواة بإضافة 4 % الومينا فقط أعطت أعلى صلادة مقارنة مع المواد المتراكبة النانوية الاخرى. وقد لوحظ ان معدل البلى او الوزن المفقود يزداد مع زيادة الحمل المسلط وزمن الانزلاق. ولكن المواد المتراكبة النانوية اظهرت معدل بلى اقل من السبيكة الاساس عند نفس ظروف التجربة.


Article
Effect of Nano Carbon Tube on the Mechanical and Physical Properties of Composites Based on Resin Route

Authors: Aseel B. Abdul-Hussein --- Emad S. AL-Hassani --- Marwa Subhi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 4 Part (A) Engineering Pages: 410-416
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this work, the physical and mechanical properties of nano composites are investigate. The nano composites consist of matrix was polyester resin and 3% volume fractions of glass fibers as reinforcement with (0.5%, 1%, 1.5%, 2 %( volume fractions of carbon nanotube as filler. Samples of nano composite materials in this research have been prepared by hand – layup. The results showed that the sample (UP+3% GF) has higher water absorption than sample net polyester. As can be noted from the results that the sample (UP+3% GF+2% CNTs) has higher value water absorption than other samples. Also can be observed from the results that the sample (UP +3%GF+0.5 CNTs) has high values of hardness (shore D), flexural strength, impact strength and fracture toughness from other (1%, 1.5%, 2%) volume fraction carbon nano tube.


Article
Photostability of PMMA-TiO2 micro composites and PMMA-TiO2 nano composites
المايكروية والنانوية PMMA-TiO2 الاستقرارية الضوئية لمتراكبات

Authors: , Z.R.Muslem زينب رحيم الشمري --- H.I.Jaafer حارث ابراهيم جعفر
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2009 Volume: 7 Issue: 8 Pages: 6-10
Publisher: Baghdad University جامعة بغداد

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Abstract

Comparison for the optical energy gap between pure PMMA , PMMA-TiO2 micro composites and PMMA-TiO2 nano composites have been investigated under uv – radiation , the effect of time irradiation (0,6,12,24,48,72,96 and 120) have been studied for these specimens to study the photic stability .The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA and PMMA-TiO2 micro composite under UV-light irradiation.

تم في هذا البخث مقارنة بين قيم فجوة الطاقة لمتراكبات البولي مثيل ميثا اكريليك وثاني اوكسيد التيتانيوم المايكروية والنانوية تتيجة تاثير اشعاع الفوق البنفسجية على هذه المواد، لدراسة الاستقرارية الضوئية تم تشعيع العينات بفترات زمنية مختلفة للتشعيع (120، 0،6،12،24،48،72،96) ساعة . اظهرت النتائج استقرارية للضوء لمتراكبات البولي مثيل ميثا اكريليك -ثاني اوكسيد التيتانيوم النانوي اكثر من العينات النقية والمايكروية.


Article
Wear and mechanical properties of epoxy/MgO-SiO2 hybrid nanocomposites
البلى والخصائص الميكانيكية لمتراكبات Epoxy/MgO-SiO2النانومترية الهجينة

Authors: Maryam Zuhair Abd-Ulwahid مريم زهير عبد الواحد --- Khalid R. Al-Rawi خالد رشاد عبد الله الراوي
Journal: Iraqi Journal of Physics المجلة العراقية للفيزياء ISSN: 20704003 Year: 2015 Volume: 13 Issue: 26 Pages: 58-63
Publisher: Baghdad University جامعة بغداد

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Abstract

Preparation of epoxy/MgO and epoxy/SiO2 nanocomposites is studding. The nano composites were processed by different nano fillers concentrations (0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.07 and 0.1 wt%). Epoxy resin and nanocomposites containing different shape nano fillers of (MgO:SiO2 composites), are shear mixing with ratio 1:1,with different nano hybrid fillers concentrations (0.025, 0.05, 0.1, 0.15, 0.2 and 0.25 wt%) to preparation of epoxy/(MgO-SiO2) hybrid nanocomposites. Experimental tests results indicate that the composite materials have significantly higher modulus of elasticity than the matrix material but the hybrid nanocomposites have lower modulus of elasticity. The wear rate was decreased in nanocomposites and hybrid nanocomposites than the matrix material and fatigue resistance was increased in nanocomposites and hybrid nanocomposites than the matrix material.

تم دراسة تأثير إضافة كل من أوكسيد المغنيسيوم النانوي وثاني أوكسيد السيلكا النانوي على الخصائص الميكانيكية وبنسب وزنية مختلفة هي 0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.07 and 0.1 wt%).). راتنج الأيبوكسي والمركب النانوي يحتويان أشكال مختلفة من الدقائق النانوية (متراكبات Mgo: SiO2), وتم إعتماد التركيب الهجيني بنسبة 1:1 وبنسب وزنية مختلفة (0.025,0.05,0.1,0.15,0.2 and 0.25%). نتائج الأختبارات التجريبية تشير الى ان المواد المركبة لديها أعلى بكثير من معامل المرونة للمادة الأساس, ولكن المتراكب الهجيني لها معامل مرونة أقل من معامل المرونة للمادة الأساس. وقد أنخفض معدل البلى في المركبات النانوية والمواد المتراكبة الهجينة عن معدل البلى للمادة الأساس ومقاومة الكلال تزداد في المواد المركبة والمواد المتراكبة الهجينة عن مقاومة الكلال للمادة الأساس.


Article
Dopant Effect on The Nonlinear Optical Properties of TiO2- PMMA Nano Composites for Optical Limiter Applications

Authors: Aya H. Makki --- Ali H. AL-Hamadani --- Mohammed Abdulridha Husien
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 5 Part (A) Engineering Pages: 1012-1016
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this paper theeffect of ZnO dopant on the nonlinearoptical behavior of TiO2-PMMA Nano composites films was studied. TiO2-PMMA Nano composites films were prepared using solution casting method then doped with different amounts of ZnO nanoparticles. Z-Scan measurements were performed to obtain the nonlinear optical response of these samples at 1064nm using CW Nd-YAG laser. The addition of ZnO nanoparticle into the Nano composites showed a great enhancement in the nonlinear optical response and decreasing in limiting threshold (10 mW)as the dopants concentration increased.


Article
Mechanical and Physical Properties of Nano Carbon Tube with Carbon Fiber Reinforced with Polyester Resin

Authors: M. Subhi --- E. S. AL-Hassani --- A.B. Abdul-Hussein
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 5 Part (A) Engineering Pages: 465-472
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

In this research, study some physical and mechanical properties of polymernano composites. The polymernano composites based on unsaturated polyester resin reinforced with carbon fibers (C.F). The samples are attended by hand lay – up method. The samples constituent were polyester resin as matrix with 3% volume fraction from carbon fiber and (0.5%, 1%, 1.5%, 2 %( volume fractions of carbon nanotube. The water absorption, hardness (shore D), flexural test, impact test and toughness fracture properties are studied. Results showed that water absorption increase with addition 3% volume fraction of carbon fiber and Carbon Nanotube, the sample (polyester+3%C.F+0.5% CNTs) has lower water absorption than other samples. The hardness (shore D), flexural test, impact testand toughness fracture for the sample (polyester+3%C.F+0.5% CNTs) has higher value for Nano- composites.


Article
Improvement some physical properties of nanocomposites reinforced by Iraqi nanoclays
تحسين بعض الخواص الفيزيائيه للمتراكبات النانويه المدعمه بالاطيان النانويه العراقيه

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Abstract

The current investigation includes the develolpment of Iraq clay to get nano structures composition and vising them as reinforced materials for Epoxy resin with weight fractions (5% , 3%, 1%).The studied speciment where prepared by manual molding method. Some Physical tests where carried out( Diffusions and Thermal conductivity ), the results showed notable improvements of the composites properties by nano particles.

شمل البحث الحالي تطوير الأطيان العراقيه للحصول على جسيمات نانوية التركيب واستخدامها كمواد للتدعيم مع الايبوكسي وحسب الكسور الوزنيه (5% , 3%, 1% ) وحضرت عينات الدراسة بطريقة القولبة اليدوية . أجريت الاختبارات الفيزيائيه ( الانتشاريه، والتوصيليه الحراريه ) فأعطت نتائج الدراسة تحسنا كبيرا في خواص المتراكبات النانويه المحضرة.


Article
Characterization of AA 6061–Alloy Composites Reinforced by Al2O3 Nano Particles Obtained by Stir Casting

Authors: Hussain J. AL Alkawi --- Abdul J. Owaid --- Batool Kadhim H.
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 7 Part (A) Engineering Pages: 792-797
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The aim of this work is generated a Nano materials havinggood mechanical properties for 6061AA-alloy.Fivewt% of Nanoparticles (Al2O3) (20-30nm grain size) were adoptees (1, 1.5, 2, 2.5 and3wt% AL2O3).The Nano composites were manufactured by stir castingtechnique. The mechanical properties of Nano composites wereobtained at room temperature and was found that the matrix hardnessis improved by 35.36%, matrix ultimate by107%, yield by36.84% andductility by 12% at 1.5wt% AL2O3.Also it was obtained that all themechanical properties of the Nano composites are higher than that ofmetal matrix. The above improvements are due to less porosity, highuniform distribution and good bounding between metal matrix andAl2O3.


Article
Effect of Water Absorption on the Compressive Strength for PMMA Nano Composites and PMMA Hybrids Nano Composites Reinforced by Different Nanoparticles Used in Dental Applications

Authors: Sihama E. Salih --- Jawad K. Oleiwi --- Alaa Mohammed.T
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 14 Part (A) Engineering Pages: 2654-2669
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Poly methyl methacrylate (PMMA), are widely used as a prosthodontic denture base, the denture base materials should exhibit good mechanical properties and dimensional stability in moist environment. In the present research, efforts were made to develop the properties of PMMA resin that used for upper and lower prosthesis complete denture, by addition four different types of nanoparticles, which are fly ash, fly dust, zirconia and aluminum that added with different ratios of volume fractions of (1%, 2% and 3%) to poly methyl methacrylate (PMMA), cold cured resin (castavaria) is the new fluid resin (pour type) as a matrix. In this work, the Nano composite and hybrid Nano composite for prosthetic dentures specimens, preparation was done by using (Hand Lay-Up) method as six groups which includes: the first three groups consists of PMMA resin reinforced by fly ash , fly dust and ZrO2 nanoparticles respectively, the second three groups consists of three types of hybrid Nano composites, which includes ((PMMA:X% fly ash)+ (1%Al + 3% ZrO2 )), ((PMMA:X% fly dust)+ (1%Al + 3% ZrO2)) and ((PMMA:X%nZrO2)+(1%fly ash+3%fly dust)) respectively. As well as, the effect of water absorption was taking into consideration in this study. The compression test results show that the values of the compressive strength with and without the effect of water absorption increased with the addition of Nano powders (fly ash, fly dust, zirconia, and aluminum). Also, the results showed that the maximum values of compressive strength reach to 286.25MPa for (PMMA: 2%nZrO2) Nano composite. Whereas the maximum values of compressive strength for hybrid Nano composite reach to 270MPa for ((PMMA: 2%fly ash) + (1%Al + 3% ZrO2)) hybrid Nano composite. Moreover, the results showed that the maximum value of compressive strength under the effect of water absorption reach to 335MPa in the Nano composite material (PMMA+2% fly dust), whereas the maximum value of compressive strength under the effect of water absorption for hybrid Nano composite reach to 362MPa for ((PMMA: 2% fly dust) + (1%Al + 3% ZrO2)) hybrid Nano composite.


Article
Investigation of Hardness and Flexural Properties of PMMA Nano Composites and PMMA Hybrids Nano Composites Reinforced by Different Nano Particles Materials used in Dental Applications

Authors: Sihama E. Salih --- Jawad K. Oleiwi --- Alaa Mohammed.T
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2016 Volume: 34 Issue: 15 Part (A) Engineering Pages: 2838-2853
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Poly methyl methacrylate (PMMA), widely used as a prosthodontic denture base, the denture base materials should exhibit good mechanical properties and dimensional stability in moist environment. In the present research, efforts are made to develop the properties of PMMA resin that used for upper and lower prosthesis complete denture, by addition four different types of nanoparticles, which are fly ash, fly dust, zirconia and aluminum that added with different ratios of volume fractions of (1%, 2% and 3%) to poly methyl methacrylate (PMMA), cold cured resin (castavaria) is the new fluid resin (pour type) as a matrix. In this work, the Nano composite and hybrid Nano composite for prosthetic dentures specimens, preparation was done by using (Hand Lay-Up) method as six groups which includes: the first three groups consists of PMMA resin reinforced by fly ash , fly dust and ZrO2 nanoparticles respectively, the second three groups consists of three types of hybrid Nano composites, which includes ((PMMA: X% nF.A)+ (1%Al + 3% ZrO2)), ((PMMA: X% nD.A)+ (1%Al + 3% ZrO2)) and ((PMMA - X%nZrO2)+(1%F.A + 3%F.D)) respectively. The hardness and flexural tests results show that the values of the hardness, flexural strength, Maximum shear stress and flexural modules increased and with the addition of Nano powders (fly ash, fly dust, zirconia, and aluminum). And the results showed that the maximum values of hardness reach to (84.166) for ((PMMA: 3%nZrO2) + (1%F.A + 3%F.D)) hybrid Nano composite, whereas the maximum values of hardness for Nano composite reach to (83.333) for (PMMA: 3%nZrO2) Nano composite. Also, the results showed that the maximum values of flexural strength and Maximum shear stress reaches to (101MPa) and (2.4738MPa) respectively for (PMMA: 2%nF.D) Nano composite. Moreover, the results showed that the maximum values of flexural modules reaches to (13.95GPa) for ((PMMA: 3% nF.A) + (1%Al + 3%ZrO2)) hybrid Nano composite, whereas the maximum values of flexural modules for Nano composite reach to (12GPa) for (PMMA-3%nZrO2) Nano composite.

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